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 A190603 Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 0 1 vertically, antidiagonally or horizontally 1
 37, 246, 2435, 36125, 815754, 27533597, 1385237002, 104775207569, 11774001696187, 1960966610305152, 486160565780600788, 179685877495264963185, 99104740635101570708266 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..23 EXAMPLE Some solutions for 4X4 ..1..0..0..0....1..1..1..0....1..1..0..0....0..0..1..0....0..0..0..1 ..0..1..1..1....1..1..1..1....1..1..1..0....0..1..0..0....0..1..1..1 ..0..1..1..0....1..1..1..1....0..1..1..0....1..0..0..1....0..1..1..1 ..0..1..0..0....0..1..1..1....0..0..0..0....0..0..1..1....1..1..1..0 CROSSREFS Sequence in context: A275750 A142445 A155974 * A142627 A142308 A105463 Adjacent sequences:  A190600 A190601 A190602 * A190604 A190605 A190606 KEYWORD nonn AUTHOR R. H. Hardin May 13 2011 STATUS approved

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Last modified November 29 01:03 EST 2020. Contains 338755 sequences. (Running on oeis4.)